GEAR PUMP GROUP 8J3635 - Caterpillar

The Caterpillar C-12 Marine Engine provide the following features:
Four cycle
Direct fuel injection
Electronic unit injection
Turbocharged
Raw/Sea water aftercooler or separate circuit aftercooler (SCAC)The electronic engine control system provides the following features:
Engine monitoring
Electronic governing
Automatic air/fuel ratio control
Torque rise shaping
Injection timing control
System diagnosticsElectronic unit injectors combine the metering of fuel (duration and timing) and the injection of fuel. Electronic unit injectors produce very high injection pressures.The Electronic Control Module (ECM) controls the amount of fuel that is injected by varying the signals to the electronic unit injectors. High injection pressures help to reduce fuel consumption and emissions. The use of this type of electronic unit injector helps to provide precise control of injection timing. The injection timing varies with engine operating conditions. This optimizes the engine's performance for starting, emissions, noise, and fuel consumption.The timing advance is achieved through the precise control of the firing of the electronic unit injector. Engine rpm is controlled by adjusting the firing duration. A speed/timing sensor provides information to the ECM for detection of cylinder position and engine rpm.The engine has built-in diagnostics that are used in order to ensure that all of the components function properly.The cooling system consists of the following components:
Gear-driven centrifugal pump
One water temperature regulator which regulates the engine coolant temperature
Oil cooler
Auxiliary water pump or a separate circuit aftercooler (SCAC)
Raw/Sea water aftercoolerThe engine lubricating oil, that is supplied by a gear-type oil pump, is cooled. The engine lubricating oil is also filtered. Bypass valves provide unrestricted flow of lubrication oil to the engine components during the following conditions:
High oil viscosity
Plugged oil cooler or plugged oil filter elements (paper cartridge)Note: Most illustrations represent typical right hand service. The C-12 Marine Engine is also available with left hand service. The following items will be located on the left side for left hand service:
Fuel filter
Oil filter
Oil level gaugeMarine Transmissions
Several manufacturers offer marine transmissions through local distributors. Lubrication oil for the marine transmission can be cooled by an optional engine mounted transmission oil cooler (certain engine ratings).Engine Service Life
Engine efficiency and maximum utilization of engine performance depend on the adherence to proper operation and maintenance recommendations. In addition, use recommended fuels, coolants and lubricants. Use the Operation and Maintenance Manual as a guide for required engine maintenance.Expected engine life is generally predicted by the average power demand, based on the fuel consumption of the engine over a period of time. Reduced hours of operation at full throttle and/or operating at reduced throttle settings result in a lower average power demand.Engine Specifications
Illustration 1 g00275578
Cylinder and valve locations
(A) Exhaust valve. (B) Inlet valve.
Table 1
C-12 Marine Engine Specifications
Cylinders and Arrangement 6 In-Line
Bore 130 mm (5.1 inch)
Stroke 150 mm (5.9 inch)
Compression Ratio 15.5:1
Aspiration TA(1)
Displacement 12 L (732.28 in3)
Firing Order 1-5-3-6-2-4
Rotation (viewed from flywheel) Counterclockwise
(1) Turbocharged Aftercooled